An EF1 tornado tore through the Riverwind Casino in Oklahoma on Oct. 21, ripping off portions of the roof and interrupting a well-attended Beach Boys Concert that was taking place inside.

The tornado and subsequent flooding caused significant damage inside the casino, destroying or damaging more than 800 games out of 2,700 in the hotel. Governor Mary Fallin, who was attending the concert, said she was evacuated twice during the course of the concert, according to News 9.

She said, when she I looked up, she saw a "huge flood of rain coming through the roof,” adding that she realized then there was significant damage to the building.

Fallin said guests at the concert were drenched in waves of water from heavy rains after the roof was blown away.

Residents evacuated

Residents and visitors inside the casino were evacuated after the tornado passed through. No injuries were reported at the casino, although other nearby hotels and buildings were affected by the tornado as well. Portions of the Riverwind Casino facade and multiple windows were also blown away by the winds.

Casino representatives said they did not have enough time to inform guests that the tornado was approaching because the alert from the National weather Service arrived at the same time as the tornado. Crews were there to make sure that all necessary precautions were taken, but the warning only arrived when the tornado was upon the building, a Riverwind spokeswoman Kym Koch said, according to Casino.

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“The power is back on, but we’re still assessing damage and we’re taking care of the patrons who are booked there for the next night or two and putting them up in another hotel,” she said on Sunday. Reservations would be canceled through Tuesday, Oct. 24, Koch added in her statement.

Assessing the damage

By Monday, casino representatives for SCR888 reported that the majority of the damaged games had been restored and that the hotel was preparing to accept new reservations later in the week. Casino representatives also said customers were still visiting the establishment, undeterred by the damage, according to Casino.

Keli Clain of the Oklahoma Department of Emergency Management said the tornado appeared to land in Cleveland county before traveling through Seminole, Comanche, Tillman, and McClain counties, according to ABC News. The NWS indicated that as many as four tornadoes ripped through Oklahoma on Saturday night.

An EF1 tornado can reach speeds of up to 110 miles per hour, Cain said according to ABC News. The Enhanced Fujita scale classifies tornadoes between EF0 and EF5 based on their wind speed.